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lateral pressure caused by contraction of the crust of the 

 earth — this side pressure upon the original flat surface 

 pressing the surface upwards as a sheet of paper laid flat 

 upon a table would bulge upward from the centre on 

 being closed in from the opposite edges. 



According to the manner and degree of pressure, the 

 appearance of the mountains and their summits is varied ; 

 and in reference to the Alps he spoke of their obtusely 

 pointed summits arranged en echelon. The same lateral 

 force that led to this form, also led to fracture in the 

 rocks ; and so, by inversions, what seem to be the newer 

 rocks are really the oldest. The Jura range of mountains 

 is not more than 3000 or 4000 feet in height, and often 

 as uniform and straight as a railway embankment. They 

 are composed of sedimentary substances, as sand and 

 gravel, and are full of graceful curves — the folds being 

 steepest on the side next to the Alps. From this it will 

 be seen that the Alpine mountains are difierent from the 

 Jura Mountains ; and these represent two systems, with 

 the Switzerland valley formed between. 



Now we have these two systems of mountains in feast- 

 em America. One extends from Newfoundland to Ala- 

 bama, and the other from the Catskills in New York to 

 Alabama. Between them is a great valley beginning 

 with the Champlain, then the Hudson, Kittatinny, Shen- 

 andoah, Great Valley of Virginia and East Tennessee. In 

 referring to the general shape of the continent, he said 

 the elevated portions are next to the oceans, while the 

 interior parts are depressed. He then described the Al- 

 pine features of the eastern mountains, — first, the New- 

 foundland district with mountains rising 2000 feet; next, 

 the middle division like that in the midst of what we now 

 are, rising to 6291 feet; and, third, the mountains of 

 North Carolina, exceedinir 7000 feet in height. In the 



